We on the 0 A.D. development team have just learned that copies of 0 A.D. on physical media, such as CDs and DVDs, are being sold on eBay, by independent stores, unrelated to us.
This is probably perfectly legal under the GNU General Public License (GPL), which 0 A.D. is released under. The license clearly states that people are free to make copies of 0 A.D. and distribute them for any price or no price, as long as they meet certain conditions, such as including the source code or indicating where it is available.
(We have not inspected these CDs/DVDs closely to verify they do meet all the conditions. So the distributors might be operating under the GPL, or not. We don’t know for sure.)
However, in either case, we wish to emphasize that 0 A.D. is available for free download and always will be. You do not have to buy it from anywhere.
The latest version to date is Alpha 10, available here. Alpha 11 is due within a few days.
Thanks for listening!